SD holders received the payout in Bitcoin via MPEx in 20 batches within 5-10 minutes 13-14 hours ago. It's unclear, when the BTC were purchased and if at all as we only could spot 20-30k coming into MPEx in a shorter timeframe before payout and more chucks some days and weeks before. I'm not very familiar with the amounts on MPEx, but people say it's not something very special, when such amounts arrive there.
The only reasonable scenario I see for buying those 130+k BTC after the payout would be a super whale who has both large amounts of BTC and fiat and who speculated to cause a selloff with the payout - 130k coins which could possibly be dumped on BTC/USD.